SQL Functions - factorial

Question

I am a beginner in SQL Functions. What is the best way to create a function for factorial in SQL Server- Say 10!

Answer 1

Here is an other method to calculate factorial value of an integer in SQL Server

 create function sqlFactorial (@int int)
 returns int
 begin
  declare @factorial bigint = 1
  select @factorial = @factorial * i from dbo.NumbersTable(1,@int,1)
  return @factorial
 end

You need to use a SQL numbers table for this solution. The Select statement updates the declared integer variable for each row in the FROM part with multiplying it with the ordered integer values